The invention relates to a disconnecting switch for a high voltage electrical substation, particularly a pantograph or semipantograph disconnecting switch, comprising a movable system of articulated arms having a contact head cooperable with a main conducting bar of a pick-up device suspended from a high voltage conductor. The contact head includes a movable main contact and a whip-type movable arcing contact controlled by an operating mechanism arranged to ensure closing of the movable arcing contact before closing of the movable main contact, and insure opening of the movable arcing contact after opening of the movable main contact.
Disconnecting switches for high voltage substations have to open and close with strong loop currents. The presence of the whip enables the current to be branched off when the main contacts open and close, which notably prevents wear of the movable contact grips. The contact surface of the bar is however damaged by the electrical arc around the contact area thereof with the whip. Tripping of the whip operating mechanism is moreover achieved by means of a complicated kinematic linkage of the disconnecting switch requiring a specific tripping adjustment.
The object of the present invention is to improve the capacity and withstand of a whip-type disconnecting switch for high voltage substations.